Calorie restriction, that is.
I always thought this was kind of a bad deal. Starve yourself by eating a paltry few hundred calories a day (of very nutrititious stuff like beets and kale and so forth) and take a lot of supplements and you have a good shot at significantly lengthening your lifespan. Great, but who wants to make it to 120 eating kale and beets?
Full disclosure: I love beets, especially the pickled kind. But you get my point. What do you get, like 400 calories? Hell, I eat more than that in the way of little "samples" that I take while cooking dinner! I'd never make it on the calorie restriction regime. I'm just not cut out for it, and I doubt that many are.
Well now, via Ray Kurzweil, here's some good news. Researchers at MIT have isolated an enzyme which is lowered when calories are restricted.
In previous research, Guarente found that rather than a slower metabolism leading to a slower rate of respiration, it turns out that respiration in yeast cells under calorie restriction goes up, not down. "A high respiration rate is intimately connected with calorie restriction in yeast," he said. "A high respiration rate activates SIR2. When respiration goes up, NADH goes down and SIR2 goes up. When SIR2 goes up, longevity happens."
This is good news, but these are early results. First off, the findings apply only to yeast. (Although it can be surprising to learn how closely related we humans are to what we would normally consider much lower forms of life.) Secondly, we're a long way from finding a way to increase SIR2 levels without the rabbit-food regimen.
But at least now we know what we're looking for.
Posted by Phil at January 2, 2004 08:55 AM | TrackBackHmmm, I don't know of any CR practitioners who only eat 400 calories a day. The moderate ones of whom I know probably eat in the 1200-1400 range; granted, there are some extremists on a couple of mailing lists who more resemble long-term POWs than healthy people, but they seem to be in the minority.
It strikes me as a given that Americans eat too much and too much of it is dietary crap - I suspect a 20% cut and improved nutrition would do wonders for the populace.
Posted by: andy at January 2, 2004 12:56 PMThe moderate ones of whom I know probably eat in the 1200-1400 range.
I guess it's all how you look at it. I just can't make myself see eating 1400 calories a day for the rest of my life as "moderate." :-)
Good points about diet and lifestyle.
Posted by: Phil at January 2, 2004 08:49 PMYour really should change that 400 calories thing - it's a big "not done the research" warning sign. 1000 kcal/day is starvation, and extreme CR for most people is 1500 kcal/day.
If you eat sensibly, you don't get hungry on 1500 kcal per day.
Reason
Posted by: Reason at January 2, 2004 10:36 PMCrikey, I was just kidding with the 400 calories thing. I've read Walford's book (referenced above.)
I don't mean to disparage calorie restriction as a practice. If it works for you, have at it. But it doesn't work for me, and I suspect it wouldn't work for many.
Posted by: Phil at January 2, 2004 11:25 PM